Heat oil over medium-high heat in a medium sized pot. Add sausage meat breaking it up with a spatula or wooden spoon into large chunks. When completely cooked, add garlic and saute for 2 – 3 minutes (careful not to let the garlic burn). Add the water, stock, beans and red pepper flakes (if using) and stir thoroughly. Simmer on low for 10 minutes, covered. Throw in kale and allow to simmer for another 10 minutes covered. Adjust salt and pepper to taste. Divide into four bowls and serve hot.